Gas trap device for an intravenous injection

ABSTRACT

A gas trap device for an intravenous injection comprises longitudinal extending passageways, an inverted, U-shaped passageway provided between and communicated with the longitudinal extending passageways, and a trap chamber provided at the top portion of the inverted, U-shaped passageway so as to prevent a gaseous material contained in a transfusion liquid from entering the body.

United States Patent 1191 1111 3,834,124 lchikawa Sept. 10, 1974 [54]GAS TRAP DEVICE FOR AN 2,597,699 5 1952 Bauer 128/214 R INTRAVENOUSINJECTION 3,332,418 7/1967 Brody 128/214 R Inventor: Hiroshi Ichikawa,Fujinomiya,

Japan Assignee: Jintan Terumo Co., Ltd., Tokyo,

Japan Filed: Nov. 28, 1972 Appl. No.: 309,976

Foreign Application Priority Data Dec. 1, 1971 Japan 46-112227 US. Cl55/159, 55/322, 128/214, 210/198 R, 210/299, 210/1310. 23

rm. 0 B0ld 19/00- Field of Search 55/52, 159, 192, 199, 468,

55/322; 128/214 R; 210/198 R, 305, 308, DIG. 19, DIG. 23

References Cited UNITED STATES PATENTS 1/1898 Wainwright 55l48 X PrimaryExaminer-Samih N. Zaharna Assistant ExaminerRichard W. Burks Attorney,Agent, or Firm-Kemon, Palmer & Estabrook [5 7] ABSTRACT A gastrap devicefor an intravenous injection comprises longitudinal extendingpassageways, an inverted, U-shaped passageway provided between and'communicated with the longitudinal extending pas sageways, and a trapchamber provided at the top portion of the inverted, U-shaped passagewayso as to prevent a gaseous material contained in a transfusion liquidfrom entering the body.

10 Claims, 11 Drawing Figures PAIENIED SEP 1 01914 SHEEI 1 [IF 3 FIG.

PAINTEU 3E?! 01974 SHEET 3 BF 3 FIG. 6

FIG. 7

FIG. 9

FIG.8

FIG.

FIG.

GAS TRAP DEVICE FOR AN INTRAVENOUS I NJECTION The present inventionrelates to a gas trap device for removing bubble or gas from atransfusion liquid during intravenous injection.

In the prior art, gas trap devices for use in blood transfusion etc. areprovided at the wall portion in the neighbourhood of a projector orneedle, for example, in a manner to form a bulging space, to permitbubble or gas to be removed from a transfusion liquid. The transfusionliquid flowed through a straight passageway is passed at the bulgingspace where bubble or gas rises and degassing is effected. In thedegassing devices as above-mentioned there are encountered drawbacksthat the rising of bubble or gas is prevented by the axial flow of atransfusion liquid and the removal of gas or bubble from a transfusionliquid is not necessarily com plete.

When an additional liquid medicine, e.g. cardiac etc. is added to atransfusion liquid in the conventional gas trap device, a rubber tube isconnected at the forward end of the degassing device and an injectionneedle is pierced through the rubber tube into the transfusion liquid. Aliquid medicine thus added to the transfusion liquid in theneighbourhood of the degassing device is transfused to the human bodywithout being intimately mixed with the transfusion liquid.

It is a primary object of the present invention to provide a gas trapdevice which is capable of more complete removal of bubble or gas andforeign material from a transfusion liquid as well as capable of anintimate mixing of an additional medicine liquid with a transfusionliquid.

The gas trap device according to the present invention compriseslongitudinal extending passageways, an inverted, U-shaped passagewayprovided between and communicated with the longitudinal extendingpassageways and a covering means for keeping air-tight the liquidpassageway, the top portion of the inverted, U-s haped passageway beingmade larger in crosssectional area than the other passageways so as toremove the bubble or gas from a transfusion liquid.

The present invention can be more fully understood from thefollowing-detailed description when taken in connection'with referenceto the accompanying drawings, in which:

FIG. 1 shows a blood transfusion set in which a gas trap deviceaccording to the present invention is used;

FIG. 2 is a view in cross section showing the gas trap device and itsconnection;

FIG. 3 is a cross sectional view taken along line II-II of FIG. 2;

FIG. 4 is a cross sectional view of the gas trap device;

FIG. 5 is a plan view of the gas trap device;

FIG. 6 is a plan view showing a filter mesh of FIGS. 2 and 3;

FIG. 7 is a cross section of a rubber plug as used in FIGS. 2 and 3;

FIG. 8 shows a holding cylinder used in the gas trap device of FIGS. 2and 3;

FIG. 9 shows a bottom view of the holding cylinder;

FIG. 10 is another embodiment of the gas trap device showing the majorparts thereof; and

FIG. 11 is a further modification of the gas trap device according tothe present invention.

Let us now explain the embodiments of a gas trap device according to thepresent invention by reference to the drawings. FIG. 1 shows adiagrammatic view of a blood transfusion set. Reference numeral 1 showsa main vessel arranged at a higher place. The main vessel may be a bloodtransfusion bottle or bag. The main vessel l is connected through apenetrating needle 2 to the blood transfusion set which is connectedthrough a drip chamber 4 and gas trap device 7 to an injection needle 5.Between the drip chamber 4 and the injection needle provided with thegas trap device there is provided a clamp 6. The adjustment of the clamp6 permits a proper amount of liquid to be injected through the injectionneedle 5 into the human body.

To explain the gas trap device in more detail the gas trap device 7 isshown in FIG. 2 to be connected at each end. The gas trap device per seis made of a synthetic resin and has longitudinal extending passageways8a, 8b and an inverted, U-shaped passageway 9 disposed at a middlebetween the passageways 8a and 8b. The inverted, U-shaped passageway 9is constructed as such that, as shown by arrows in FIG. 2, a liquidintroduced from the passageway 8a is, upon contact with an abutting wall10, passed upwards through a bore 11a to a trap chamber provided at thetop portion of the inverted, U-shaped passageway and, after diffusion,is flowed downwards through another bore 11b to the passageway 8b. Thebottom portion of the gas trap device 7 confronting the trap chamber 12is flattened so as to effect an easy attachment to the human body. Thetrap chamber constitutes a cylindrical space surrounded by a holdingcylinder and has an extremely larger capacity than the amount of liquidpassed beyond the inverted, U-shaped passageway 9. When the liquid ispassed through the trap chamber 12 bubble or gas presenttherein istrapped within the trap chamber.

As shown in FIGS. 8 and 9 a holding cylinder 13 has a pair of cup-shapedbores 11a, 1112 at the bottom portion thereof and fitted within thecylindrical wall of the gas trap device 7 per se. The holding cylinder13 has an annular shoulder 15 at the bottom portion of the cylindricalwall 14 and is so designed as to securely hold a filter mesh on the topsurface of the abutting wall which is in the same plane as the annularshoulder. As a filter mesh use is made, for example, of a disk-likefilter mesh (37 u pore size) of 9 mm in diameter. Within the inner wallof the cylindrical wall 14 there is provided a projection which isfitted into a groove 18 provided in an outer wall of the holdingcylinder 13. This prevents any displacement of the holding cylinder 13with respect to the cylindrical wall. As will be understood from thedrawings the bores 11a, 11b are arranged at each side of the abuttingwall 10.

As shown in FIGS. 2 and 3 a member such as rubber plug 19, through whichadditional liquid is introduced, may be sealed, as required, over theupper opening of the trap chamber 12. Before assembly the member 19 isin a position shown in FIG. 7 and has a plate-like portion 20 aroundwhich a cylindrical mating side wall 21 extends downwards. When themember 19 is assembled, the plate-like portion 20 is fitted over theopening of the cylindrical wall 14 to permit the mating side wall to beresiliently snap-fitted in a liquid-tight fashion over the cylindricalwall due to the resilience of the rubber plug 19. In this case aprojection provided on the inner end portion of the mating side wall issnap-fitted over an annular projection 23 of the cylindrical wallportion 14 to permit the under-surface of the plate-like portion 20 tobe urged downwardly relative to the top end of the holding cylinder 13,thereby securing the'holding cylinder in place. At the liquid enteringend of the gas trap device 7 there is connected one end of a tube 24 theother end of which is connected to the drip chamber 4. Over the outerperiphery at the liquid discharging end of the degassing tube 7 atapered cannula a is fitted having a needle 5.

When the gas trap device of the above-mentioned structure is used,transfusion blood can be supplied from the tube 24 with the trap chamber12 kept underside and any air trapped within the trap space rises-in theliquid passageway 8 and is degassed out of the needle 5. In this case,the trap chamber is filled with the liquid. Then a transfusion operationis effected with the trap chamber kept underside. When the fluid risesalong the inverted, U-shaped passageway 9 bubbles of gas present in theliquid rise within the trap chamber 12 to permit the rising of thebubbles of gas to be promoted with the result that it is easily trappedwithin the trap chamber. This assures a degassing operation. Filtermeshes 16 are provided one at the entry side and one at the dischargeside of the inverted, U-shaped liquid passageway. Therefore, atransfusion liquid must be passed through filter mesh '16 and bore 11ainto the trap chamber and be passed through filter mesh 16 and bore 1112out of the trap chamber. Since the liquid is passed through the filtermesh twice, any foreign matter is removed as well as a degassingoperation is promoted due to the presence of a filter mesh at thedischarge side of the inverted, U-shaped passageway. The filter mesh isusually required in the blood transfusion. However, it is not requiredin the transfusion of preliminarily refined liquid medicine etc.

Whenan additional liquidmedicine is to be added to the transfusionfluid, a transfusion needle is pierced through the portion 20 of therubber plug into the trap chamber '12. Since the needle is pierced intothe eddy transfusion liquid caused by the inverted, U-shaped passageway9 a liquid mixing operation is further promoted, which is partly aidedby the presence of the filtering mesh. Thus, a sufficient stirring oragitation is assured. When a liquid medicine is added through a tubbertubeconnected at the drip chamber side of the gas trap device a mixingoperation is effected at the inverted, U-shaped passageway and trapchamber 12 and filter mesh 16.

H6. shows another plug member through which another liquid is added bymeans of a needle to a transfusion liquid. Into the opening of acylindrical wall 25 there is fitted a plug member 26 over which athermally shrinkable tube 27-may be fitted. it. isalso possible to l 4fused or adhesively bonded to the top end of the cylindrical wall 28. Afilter mesh 30 may be adhesively bonded to the shoulder portion andabutting wall 10.

In the above embodiments, use is made as a filter mesh of such materialas nylon mesh. However, as a filter mesh, there may be used a variety ofporous materials such as, for example, polyvinyl chloride, polyethylene,polypropylene, polycarbonate, those sintered or compression formedmaterials made of the other powdered synthetic resins, as well asinorganic porous materials such as, for example, fiscuit diatomaceousearth,

glass fiber, asbestos, metal sintered body etc. These porous filtermaterials have a porous diameter of 20-150 u. Preferable is a filtermaterial capable of eliminating particles whose size ranges between 3and 80 u. These porous materials, unlike those flattened meshes, arecapable of catching any foreign matter not only at the surface but alsoat the inside thereof. Since the foreign 'matter is caught in adispersed manner, lesser clogging of the mesh is encountered as comparedwith the I amount of the foreign matter as caught. Even if the form anouter threaded portion at the periphery wall of the cylindrical wall 25which is in mesh with an inner threaded portion provided at the innerperiphery of the plug member. It will be clear that the other anchoringamount of the foreign matter so caught is increased, the

flow resistance of the liquid is not so increased, thereby assuring along service of life. The foreign matter once caught does not tend topass through the filter mesh.

As will be understood from the above explanation the present inventionprovides a gas trap device for liquid transfusion capable of assuredlyremoving bubble or gas from a transfusion liquid as well asaddinganother liquid to the transfusion liquid. This assures an easytransfusion operation as well as easy addition of another liquid to thetransfusion liquid without involving any dangerous result.

What we claim is:

1. A gas trap device for an intravenous injection comprisinglongitudinally extending passageways, an inverted U-shaped liquidpassageway provided between and communicated with said longitudinallyextending passageways, and covering means provided over the invertedU-shaped liquid passageway for keeping airtight the liquid passageway,the top portion of said in verted U-shaped liquid passageway beinglarger in cross-sectional area than the other passageways, therebyproviding a gas trap chamber.

2. The gas trap device as claimed in claim 1 wherein said covering meansis a rubber plug through which additional liquid can be introduced.

3. The gas trap device as claimed in claim 1 in which said coveringmeans is a plastic plate.

4. The gas trap device as claimed in claim 1 in which a filter mesh isprovided in said U-shaped liquid passageway.

The gas trap device as claimed in claim 1 in which a filter mesh isprovided at the inlet to said U-shapcd liquid passageway and anotherfilter mesh is provided at the outlet of said U-shaped liquidpassageway.

6. The gas trap device as claimed in claim 4 wherein said filter mesh isa plastic mesh.

7. The gas trap device as claimed in claim 4 wherein said filter mesh isa disc of porous material.

8. The gas trap device claimed in claim 4 wherein said gas trap chamberis surrounded by a holding cylinder which serves to hold said filtermesh in position relative to said Ushaped liquid passageway.

9. The gas trap device claimed in claim 4 wherein said filter mesh isthermally fused to the bottom portion of said gas trap chamber.

10. The gas trap device claimed in claim 4 wherein said filter mesh isadhesively bonded to the bottom portion of said gas trap chamber.

1. A gas trap device for an intravenous injection comprisinglongitudinally extending passageways, an inverted U-shaped liquidpassageway provided between and communicated with said longitudinallyextending passageways, and covering means provided over the invertedU-shaped liquid passageway for keeping airtight the liquid passageway,the top portion of said inverted Ushaped liquid passageway being largerin cross-sectional area than the other passageways, thereby providing agas trap chamber.
 2. The gas trap device as claimed in claim 1 whereinsaid covering means is a rubber plug through which additional liquid canbe introduced.
 3. The gas trap device as claimed in claim 1 in whichsaid covering means is a plastic plate.
 4. The gas trap device asclaimed in claim 1 in which a filter mesh is provided in said U-shapedliquid passageway.
 5. The gas trap device as claimed in claim 1 in whicha filter mesh is provided at the inlet to said U-shaped liquidpassageway and another filter mesh is provided at the outlet of saidU-shaped liquid passageway.
 6. The gas trap device as claimed in claim 4wherein said filter mesh is a plastic mesh.
 7. The gas trap device asclaimed in claim 4 wherein said filter mesh is a disc of porousmaterial.
 8. The gas trap device claimed in claim 4 wherein said gastrap chamber is surrounded by a holding cylinder which serves to holdsaid filter mesh in position relative to said U-shaped liquidpassageway.
 9. The gas trap device claimed in claim 4 wherein saidfilter mesh is thermally fused to the bottom portion of said gas trapchamber.
 10. The gas trap device claimed in claim 4 wherein said filtermesh is adhesively bonded to the bottom portion of said gas trapchamber.